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  • 2003 Volume 5 Issue 4
    Published: 25 December 2003
      
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  • ARTICLES
    Discussion on Theory and Practice of Management Mechanism of Data Project
    ZHAO Dengfeng, WANG Xingkui, JIANG Yan
    2003, 5(4): 10-15.
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    Data itself can make up an independent data project without an application system Up to now, it is quite urgent to introduce management mechanism for data project in China This paper first analyzes the various problems in data project construction in our country and gives the necessity of practicing data management Then, according to the particularity of data project and practice on data project management, some discussions on the mechanisms, contents, and flow process of data are presented The specialty, the difficulties and the operating regulations are discussed in detail.
  • ARTICLES
    Geometric Object Implementation of Spatial Database with OCCI
    WU Jie, LU Feng, TANG Jingtian, CHENG Changxiu, YUAN Zhengwu
    2003, 5(4): 16-21.
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    Accessing and manipulating the spatial data efficiently stored in the enterprise relational database management systems is an important task f or GIS platforms and engineering Among the interfaces provided by Oracle, Oracle Call Interface (OCI) and Oracle C++ Call Interface (OCCI) are welcomed for their outstanding advantages With a detailed analysis on OCI, OCCI and Object Type Translator (OTT), the authors set forward an object oriented method accessing and manipulating the SDO geometric objects in Oracle system with OCCI and OTT technologies, and conducted an experiment with Oracle 9i The method allows users to construct their own geometric model with inheritance from SDO geometric model, thus avoiding the spatial information transformation between SDO geometric objects and user defined geometric objects during uploading and downloading the spatial data Mo reover, the spatial operators and spatial aggregate functions of Oracle Spatial can be used sufficiently.
  • ARTICLES
    A Study on Method for Quickly Establishing the Background Database of Flood Disaster Region
    BI Jiantao, CHI Tianhe, HE Jianbang
    2003, 5(4): 22-24.
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    Using a new method and working flow,with the help of the ParGIP, a parallel rem ote sensing images processing software, and the ArcGIS software, we can quickly establish a background database of the flooding disaster region, which include remote sensing images and vector data The establishment of the background database can be divided into three parts The first step is the land use classification of the researched area and the boundary extraction of each class using ParGIP, in this step we can get the black white map of each land use class. The second step is the creation of the vector map of each land use class' black and white map using ParGIP, in this step we can get vector data of all classes very quickly. The last step is the creation of the vector data of the administrative boundary using AlgoLab PtVector software to scan and vectorize the paper map With the establishment of the background database of the research area, it will be useful to the monitoring and evaluating of the sudden disasters Using the SAR image of the disaster area, we can extract the flooding area from it and put it into vector format; then with the help of ArcInfo we can overlay different vector data together and get the different valuable results such as the flooded area of each county and of each land use class very quickly According to the experiment in the Poyang Lake region, this method can promote the speed and the efficiency of the monitoring and evaluating of flooding disaster to several times.
  • ARTICLES
    Marine GIS Field Data Model
    ZHANG Tianyu, ZHOU Chenghu, SHAO Quanqin
    2003, 5(4): 25-29.
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    Marine GIS has become one of the important developing domains of GIS sciences Both scholars in GIS and in oceanography are interested in it The basic representation is considered as one of the most important problems This article presents a data model to solve the problem It includes three database: basic database, data warehouse and database for marine phenomena; two data analyzing mode: data pre disposing and feature analyzing It uses multi level extended grid data structure with two kinds of global grid scheme One is equal angle, the other is equal area grid scheme They have some new marine chara cteristics.
  • ARTICLES
    The Research of Anhui Tourism Information System Based on GIS
    ZHONG Lei, ZHA Liangsong, HU Wei
    2003, 5(4): 30-33.
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    To meet the development requirement of tourist industry in Anhui, bring tourist industry into a new supporting industry and construct much better tourist circumstances,through coordinated development, this article studies and designs Anhui tourism information system supported by GIS It mainly explains the designing aim and principle, constructing process, primary function and the characteristic of the system based on GIS technology The successful construction of the system will benefit large numbers of users and have an important influence on both the development of Anhui tourism and the improvement of its soft circumstances.
  • ARTICLES
    Macro Agriculture Decision Support System with WebGIS and Its Applications
    QIAO Yanyou, WU Xiaobo
    2003, 5(4): 34-37.
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    With the idea of agricultural information sharing, benefits of macro agriculture decision support are analyzed, a prototype macro agriculture decision support system is built, and its application to restructure crop planting is made successfully Through agriculture statistics,a large amount of agricultural information has been collected and archived each year. In the information era they are now stored in databases and are shared all over the country via the web Hidden in the large databases, the mass valuable knowledge can be of great help for decision making so as to promote sustainable agricultural development The utilization of the hidden knowledge needs a decision support environment for ordinary users to use resources distributed across the web to analyze the data, to detect the knowledge, to visualize the knowledge for decision support The prototype system is a web based one, it is composed of the distributed agricultural databases, the model bases, the decision support process generator, and the reporting and visualization tools Within the distributed databases, different data servers across the country are linked to provide high efficient data services There are many data analysis models inside the model base, and they can be used to analyze the raw data The decision support process generator is used as an interface to form practical decision supports, it is in a flowchart process where models are combined with data in each step to make an analysis Reporting and visualization tools are used to form standard statistical tables, graphs, and thematic maps for gaining direct knowledge of the result With the help of this prototype system, different decision support processes can be formed easily and can be run to get scientific background for decision supports A decision support system for restructuring of plantings has been generated and run to demonstrate the benefits of the prototype system.
  • ARTICLES
    The Information System of Precision Rice Cultivation (PRC/INFO1.0):Its Structure Management and Application
    CHEN Shenbin, LIAO Shunbao, WANG Juanle, YANG Xingwei
    2003, 5(4): 38-42.
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    Precision agriculture is one direction of the world agricultural development in the new century and also is the case in China Precision agriculture in China is in the initial stage Rice yield amounts to about 40% of the total output of grain in China It is of great significance for better utilization of agricultural resource and environmental protection if the precision rice cultiv ation is realized The experimentation of precision rice cultivation has been carried out in experimental and demonstrated base of precision agriculture on Wusi Farm in Fengxian County of Shanghai The experimentation has got the support from Chinese Academy of Sciences, Shanghai Agriculture, Industry & Commerce General Corp and Shangh ai Meteorology Bureau The experimental results show that the applied chemical fertilizer decreased by 15%, per unit area yield of rice increased by 8%,and the total income increased by 18% compared with paddy fields without practising precision cultivation Information system for precision rice cultivation (PRC/INFO) is the kernel for realizing precision rice cultivation PRC/INFO 1 0 is finished by now The software modules included the following: (1) management of database; (2) conversion, management and analysis of paddyfield spatial data; (3) decision making of paddyfield management and fertilization; (4) economic evaluation of precisionrice cultivation; and (5) visual output of fertilization plan The module of paddy field spatial data management among the system is only based on SupperMap 3 0, ot hers are developed by ourselves This paper introduces construction, flow progress, main function and technol ogical characteristics of the system The system was only used in experimental filed of Shanghai by now It should be improved step by step.
  • ARTICLES
    Design and Development of Nandagang'sWetland Tourism Information System
    WANG Jianhua, HU Wenliang, ZHANG Yiwen
    2003, 5(4): 43-46.
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    Adapting to the need of Nandagang's wetland eco tourism, a software of Nandagang's wetland tourism information system (NWTIS) was specially designed and developed According to the idea of serving Nandagang's wetland eco tourism, integrating language editor and visual database management of Microsoft Visual Basic, with vector map output function of MapInfo, the authors have developed the NWTIS which realized query, analysis and display of a large mount of spatial and attribute data This paper introduced the details of design and development of the NWTIS, including the designing ideas, designing principles, development and application environment of the system,as well as design and development of its function modules,etc.
  • ARTICLES
    The Research of Extending Components GIS——The Design to Extend Component Using Outgoing Interface
    RONG Kai, SHEN Jing, YANG Zuhu
    2003, 5(4): 47-52.
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    With rapid development of GIS in recent years, the trend of components GIS has become more and more popular But because of the encapsulation essence of the object oriented model, programmers can only use the interfaces to communicate with the object without knowing anything about the realization details They will get into dilemma when they encounter those functions that GIS components can not realize In this circumstance, the outgoing interface defined by the GIS components can be used to extend the GIS components to realize those functions This article will introduce how to use the outgoing interface to customize the symbols in MapObjects and illustrate the mechanism of the process Meanwhile, the article will also introduce how to add an outgoing interface when developing GIS components Finally, the article discusses the possible trend of this mechanism.
  • ARTICLES
    The Influences of Grid Technology on the Development of GIS
    XIA Shudong, LI Qi, CHENG Jicheng
    2003, 5(4): 53-56.
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    The Grid refers to an computer network infrastructure that enables the geographical distributed computing resource,storage resource,network resource,software resource,data resource,information resource… etc, to be integrated into a logistic one. Grid technology as a new generational Web technology,will deeply influence the development of Geographic Information System(GIS), especially on Web based large scale GIS,which is the key component of digital city .The infl uence is fully analyzed from six respects in this paper,and some conclusion are listed in this paper. Grid computing technology provides powerful computing resource support for data intensive spatial analyses,which is the key function of GIS, especially in GIS based simulation fields,such as urban transportation sim ulation and atmospheric pollution simulation. Data Grid technology provides integ rated solution for the storage,analyses,management,movement of large scale spatial data,and Spatial Data Grid(SDG) is the most powerful style of National Spatal Data Infrastructure(NSDI). Grid technology also provides a new method for real time scene rending and large scale scene data storage in Virtual Reality Geograp hic Information System(VRGIS),which is very promising in Virtual Geographic Envi ronment(VGE) construction. VRGIS can be used in fields such as martial flight si mulation and virtual city So Grid technology will speed the multi dimension tre n d of the development of geographic information system.With Grid technology,we ca n solve the interoperability problem more easily,which includes data interoperab ility problem,semantic interoperability problem and system interoperability prob lem. The software development model by using agent components that quarter at gr id node to build up applicatonal software danamicly in large scale geographic i n formation system domain will deeply influence the menthod of geographic informat ion system applicatonal software development. Finally,we advice to boost the dev elopment of the geographic information system industry by building up National S patial Information Grid(NSIG),which is the most important part of digital city. All in all, Grid can provide integrated geographic information application and/o r services for geographical distributed users at different organizations as if i t were a super WebGIS.
  • ARTICLES
    Architecture of Grid-GIS and Its Key Techniques
    SHEN Zhanfeng, LUO Jiancheng, CAI Shaohua, ZHENG Jiang, CHEN Qiuxiao, SUN Qinghui
    2003, 5(4): 57-62.
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    Based on the application of Grid Computing on Geographical Information System (GIS), this paper analyzes and expatiates current application of Grid Co mputing on GIS and the problem it faces With Middleware technology, it presents the architecture of Grid GIS and lists the techniques it needs After analyzing the common problem and the development of Grid GIS, this paper points out that the distributing architecture, which is based on GML internet language and Web Service technique and Middleware,is a main developing direction of current GIS software and the best way to solve the problem it faces, then we discuss its realization process.
  • ARTICLES
    A New Technique on Spatial-temporal Data Fusion and Construction of Grid Data Platform
    LIU Mingliang, TANG Xianming, ZHUANG Dafang, LIU Jiyuan
    2003, 5(4): 63-68.
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    Spatial temporal data fusion is a key technology in studying the spatial pattern and processes of geographical objects and phenomen on We designed a database platform on land use and land change based on one squire kilometer resolution grid frame in the process of establishing national resources and environmental databases This data arrangement method has the following priorities:(1)it can decrease the data storage requirement without losing the area information Also it can meet the needs for regional analysis;(2)it can be easily applied to store temporal series data, to obtain the change information and display the results;(3) it can be applied to regional land use change study and integrated driving forces analysis by combining other data sources;and (4)it can also be used to scale up from small scale to large scale Based on spatial aggregation process, the national and global analysis can be realized from regional data and results.
  • ARTICLES
    The Method of Flood Disaster Risk EvaluationBased Upon Data of Grid Square
    ZHANG Chao, WAN Qing, ZHANG Jiquan , Norio Okada, LI Huiguo
    2003, 5(4): 69-73.
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    In this paper the flood inundation caused by the Tokai heavy rainfall in Sept 2000 in the district of Nagoya City of Japan is used as a case of study Firstly, the history and structure of grid square statistical data in Japan is reviewed in detail, and the methods of creating these grid squares of different levels automatically are developed using geographical information system technique And then based on the theory of two dimensional shallow flow hydrodynamics, the numeric model is developed which is used to stimulate flood inundation after dike broken of Shin River Through integrating the GIS and hydrodynamic model, the values of velocity and depth in each 50m mesh are calculated at different time intervals These factors can be used as the flood risk indicator in practice and are very useful for decision making in the emergency period Then the three dimensional visualization of the inundation process is finished Also the exposure value of different properties are evaluated in each 500m mesh And then the economic losses caused by flood disaster are evaluated The results will be beneficial to evaluate the risk of every place in the flood plain and determine the insurance rate in the future because it can provide the common standard which is based on the same kinds of mesh Also it provides an example which will be helpful to using the grid square statistical data in the other study fields such as urban planning and disaster reducing.
  • ARTICLES
    Mechanism Analysis of Interpreting the Digital Space of the Earth ——The Future of Geographic Research
    CHEN Xing
    2003, 5(4): 74-76.
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    Geography is one of the important disciplines for the development of human society In comparison with the available large number of research about geography's future, a little is known about interpreting the digital space of the earth Based on the human social developing issues sustainable development, economic globalization and human actions in information society, the future of geography was studied by means of geographic analysis spatial view, time view, scale view, dynamic view, synthesis, and expression The results showed that there are four changes in future geography: first, research object of geography changes from real geographic space to digital geo space mainly; second, space time view of geographers changes from three dimensional space to multidimensional space and from un reversible time to reversible time; third, research tools change to remote sensing, geographic information system, global positioning system, web and computers;and fourth, the research methods change to simulation, optimization, and control of decision making This article puts forward that the surface of the earth will be studied comprehensively by interpreting the digital space of the earth, which it brings the quantitative analysis of geography to mature.
  • ARTICLES
    On the Intelligent Processing Techniques of Remote Sensing Application
    DAI Changda, JIANG Xiaoguang, TANG Lingli
    2003, 5(4): 77-82.
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    Raw images obtained by whatever earth observation systems are the comprehensive reflection of magnetic spectrum characteristics of surface objects The primary images produced through systematic processing in remote sensing ground station still contain various errors in geometry and radiation because of the influence of atmospheric and topographic conditions And the information from various objects mixes together and influences each other Therefore, what the primary image provides is only data instead of information This data must be reprocessed to get high quality image and useful information suitable to different special applications However, the specialties of most researchers who are engaged in remote sensing image processing are computer, electronics etc They have not enough knowledge in application fields and can’t understand well the rich and valuable information which the remote sensing data of different sensors and different dates contains Apparently, even an excellent expert on image processing can’t complete processing tasks effectively to meet the demands of various applications Thus, up to now, the huge and valuable remote sensing data haven’t been used fully and effectively We think that the remote sensing image processing should be divided into two parts, systematic processing and application processing They are two parts of remote sensing processing, being both closely related and differing from each other The purpose of systematic processing is to improve the quality of image on the whole While that of application processing is, according to concrete application purpose and task, to carry out the comprehensive and object oriented processing so as to analyze and extract thematic information accurately and effectively This paper discussed the general method and procedure of remote sensing image application processing, and showed some successful examples of using it in forest fire detecting, rapid response of flood, city expansion investigation, soil resource survey and management, and dynamic monitoring of landuse.
  • ARTICLES
    On Line Prediction Technique to the Strong Earthquake Event——Thinking over Jiashi-Bachu Earthquake of M6.8
    LIU Defu, KANG Chunli, LI Lingyi, GAO Guoying
    2003, 5(4): 83-87.
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    An earthquake(M6 8) occurred on Feb 24,2003 in Jiashi and Bachu counties of Xinjiang of China This earthquake(epicenter:N39 5°and E77 2°) produced many casualties,over 2000 injured and over 200 died, as well ten thousands of buildings destroy Its occurrence shows again the importance of precise prediction Taking this event as an example, the paper raises a new technique involving 3 elements for predicting earthquake,i e ,tracking each information in element order and step by step It's process as follows:The first step is the precise judgment of seismic intensity (magnitude) According to the “Gutenberg Law”, there existed a linear relationship bet ween the different seismic magnitudes(M) and the sequence number(N),i e , “Log N = a-bM” Because the seismic actions are of self exciting characteristic, so we can base on the historic seismic information and establish a self exciting mathematical model for predicting the forth or the next time earthquake magnitud e According to the result of modeling and calculating to Xinjiang of China, we can precisely predict out that an earthquake of M5 4 will occur in Xinjiang followed by an M6 8 strong earthquake event in 2003 The second step is the precise judgment of risk region A lot of investigations show that there exists heat radiation omen before a strong earthquake,especi ally in epicentral region How to moniter this thermal omen information before earthquake for judging risk region in short term,the paper suggested to use OLR (Outgoing Longwave Radiation) information which comes from the NOAA satellite remote sensing As a result,we found that the most high value of monthly departure of OLR were present at the Jiashi epicenter region in January of 2003,and reached +21 9(W/m 2) which is not only the highest value in whole Xinjiang, but also breaks through the historic record The last step is the precise judgment of the imminent earthquake time A good many of investigations of earthquake in situ shows that the small pertubation in external factors, such as atmospheric pressure etc , can trigger the strong earthquake, especially at the imminence time We found that the pressure vari ograph (24 hours) at Jiashi epicentral region had changed +6 5(hp) on February 21,2003, i e , three days ahead of the Jiashi earthquake (M6 8) The process above mentioned is not only gradually reflecting earthquake preparat ion and evolution, but also gradually revealing it's omen features We believ e this predicting technique on line based on combining satellite remote sensing with ground information to be of far reaching importance.
  • ARTICLES
    Research on Raster-to-Vector Conversion from Remotely-sensed Classified Images for Ecological-environmental Mapping: a Case Study of the Coast Zone of Fujian Province
    CHEN Yunzhi, CHEN Chongcheng, LING Feilong, QU Min
    2003, 5(4): 88-93.
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    Raster to vector conversion from remotely sensed classified images is pre re quisite and kernel processing for ecological environmental mapping and its applied spatial analysis In this paper, the deficiency and limitations of procedures and their resulting land cover/land use data,associated with conversion to vector coverage database from remotely sensed classified images fore ecological environmental mapping, were explored in detail at first These procedures were qualified as ready to wear or pis aller, which applied built in function modules within some remote sensing processing and analysis systems, such as ERDAS,PCI Then a new universal approach to raster to vector conversion from remotely sensed classified images for ecological environmental mapping was delineated based on the paradigm of combining remote sensing processing & analysis systems (such as ER Mapper) with GIS (ArcGIS, for example), and its processing flowchart also presented using an pilot TM classified image in the coast zone of Fujian Province The classified images were labeled as 13 types of land cover/land use by automatic statistic classification and manually on screen digitalized in the form of ecological environmental investigation and dynamic evolution monitoring Finally, the accuracy evaluation of conversion was made through a transfer matrix between original classified images and vector to raster re converted images, and it turned out that the ratio of keeping to original land cover/land use type came up to 94 63% within the global classified image.
  • ARTICLES
    Remote Sensing for Archaeology in Several Typical Areas of the West China
    LI Xianhua, ZHOU Jianhua, LIU Shuren, YAO Meng
    2003, 5(4): 94-96.
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    As the remote sensing archaeology integrates the techniques of remote sensing and field archaeology, the study mentioned in this paper ulteriorly integrates remote sensing archaeology with technique of virtual reality and the multiple subjects correlated with archaeology Sustained by the integration, the evolvement of ancient geographical environment whose features kept in some historic remains and the relationship among these remains will be studied There are such main characteristics in the study as intersection, penetration and amalgamation of physical and social sciences along with the archaeological practices in typical areas, study of the new theory and high tech of remote sensing archaeology and so on From aspect of basic research, the main contents of the study are the spectrum features of the remote sensing archaeological objects, the mechanism of remote sensing archaeology such as extracting faint information from these underground objects and making out translating mechanism of their information and theoretical system and technical criterion of remote sensing archaeology From a spect of technical development, the main symbols are these studies on earth ori ented observation under whole spectrum, whole weather, and whole time and with various platforms, on establishment of the processing and analyzing system of remote sensing archaeology information and the system will be symbolized with definitely perspective capability, multiple dimensions in time and space, multiform information resources and on digitally virtual expression of typical historic remains and the anversion of geographical environment From aspect of applications, the targets are investigation of distribution of the historic remains in the typical areas of West China, establishment of the information system of important historic remains in these typical areas, discovery of the temporally and specially distributional rules of the historic remains in these typical areas and enrichment of the civilized history of West China.
  • ARTICLES
    The Discussion on Related Technical Issues of Fast Soil Erosion Remote Sensing Investigation
    QIAO Yuliang
    2003, 5(4): 97-100.
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    The article reviews more than 20 years out of 80 years of application and research work of remote sensing technology (RS), geographic information system (GIS) and global positioning system on soil erosion, and briefly introduces and comments on the technical approaches during the process of erosion investigation at different stages. It aims at making soil conservation monitoring workers understand “3S” application in soil erosion investigation process, and have a clear direction for future application study. The application of RS, GIS and GPS to soil erosion fast investigation is a beneficial attempt for the applied of Hi tech to production reality, and also is a frontier for the applied study of “3S” in water and soil conservation. Soil erosion investigation is a quite complicated task. This article, based on the experience of summary on erosion remote sensing investigation at different periods of time, aiming at the existing technical problems in the third remote sensing investigation on soil erosion, carries out an analysis and puts forward corresponding suggestions so as to consult with colleagues and to provide a reference for decision making.
  • ARTICLES
    On Geographic Framework of Geo-informatic Tupu Method
    ZHANG Hongyan, WANG Qinmin, LU Xuejun LI Huiguo
    2003, 5(4): 101-103.
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    The authors propose a conceptual framework on Geo Informatic Tupu method from the point of view of geography in the paper We especially emphasize that Tupu is not only a way for presentation, but also a method of analysis It integrates cognition, graph and method Some key concepts and their meanings are briefly discussed firstly Then the authors give a general review on application of graphic methods from other fields such as physics and biology, especially Chinese ancient Fengshui (geomantic) theory and cartography Geo Informatic Tupu is a junction, which can connect traditional geography and modern technology The paper analyzes the main problems in geography from aspects of philosophy, theory and methodology, and points out that holistic thought should be regarded as philosophic basis for the method As beginning of study on the method, building regional spatial unit and their hierachical system, setting up imagine feature standard for geogra phic elements by remote sensing technique and finding out ways of presentation for Geo Informatic Tupu, all of these are considered as main directions They will be essential to clarify the method.
  • ARTICLES
    Computer Aided Grassland Cartography with ArcMap Software
    HOU Xiyong
    2003, 5(4): 104-109.
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    The whole process of the computer aided cartography of the grassland thematic maps using the ArcMap software, which is a part of the ArcGIS8 1, was introduced in detail in this article, and the particular problems that had been met during the work were illustrated carefully The grass data all over the country was got from the interpretation of Landsat TM remote sensing images that had beenph otographed during 19992000 The background factors being included in this grassland thematic map cartographic work are residents, administrative boundaries, road system, railway system and fluvial system. And all these background factors have the data sets with spatial resolution of 1∶500 000 Both the grassland data sets and the geographical base maps were made by the ARC/INFO software and were stored as ARC/INFO coverage format files Based on these data sets, the cartographic work was divided into two parts The first part was the cartography of grassland based on all the provincial administrative units except Taiwan province, Hong Kong special municipality and Macao special municipality because of the unavailability of their grassland data sets An atlas including 31 maps in total was got at the end of the work The second part was the cartography of grassland based on the 1∶500 000 scale spatial division of the whole country An atlas including more than 210 maps covering the whole terrestrial section as well as the section of large islands was got at last The first part of the work was much complicated than the other and more flexibility was needed However the second part of the work had a much heavier workload than the first one In view of these obvious differences between the two parts of the work, different workflows were designed respectively to efficiently accomplish them In addition, the computer hardware system and the software environment, especially the ArcMap software needed by the cartographic work were introduced and discussed in detail in this article.
  • ARTICLES
    DEM-Based Landforms Extraction and Application ——A Case Study in the Hilly-gully Areas of the Loess Plateau
    ZHU Hongchun, ZHANG Youshun, TANG Guoan, YUAN Kansheng, LI Xiaoyin, YI Hongwei
    2003, 5(4): 110-113.
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    From the point of view of the landforms’cause of formation, landforms configuration and land use, regional characters of the three types of landforms in the hilly gully areas of the Loess Plateau are analyzed Approach and technology for automatic extraction of landforms are discussed using DEM as data resource,ArcView as instrument and regional characters of different landforms as basis taking Liujiagou River Basin in Suide County of northern Shaanxi Province as a case This research discovered that the approach and technology for automatic landforms extration using DEM is a high efficient method which is very important to guide biologic rescue of sloping plantation, govern water and soil conservation and test land use dynamically.